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While at Miami, Florida, early in 1919, the, author again 
visited the mangrove swamp on the border of Brickeirs Ham- 
mock, for the purpose of securing additional material of several 
interesting species of Orthoptera which, in 1915, had been found 
therein, — i. e. Hygronemobius alleni (Morse), Anaxipha scia Heb- 
ard and Anaxipha imitator (Saussure.) 1 While searching for spec- 
imens of the second species, about the mangrove shoots which 
projected from the muck and tidal litter, some of the latter 
was overturned and a specimen of Euborellia revealed. This indi- 
vidual soon was seen to be different from annulipes (Lucas), 
the only species of the genus hitherto known from the United 
States, and vigorous efforts were vainly made to find other exam- 
ples. Several days later the spot was revisited and yards of the 
litter carefully lifted and sifted. Hours of such work result- 
ed in our securing five males, three females and several immature 
specimens of the species. These were found under seaweed and 
sea-grass, drifted in to the edge of the normal high tide, us- 
ually between the lower matted layers, near the wet, mucky 
ground. The species was local, but never in colonies, as is us- 
ual for Anisolabis maritima (Gene), two specimens of which were 
found in the same place. The area in which the species occurred 
is shown in the accompanying illustrations (pi. XVIII, figs. 1 
and 2). 

Comparison of this material with a female of Euborellia 
ambigua (Borelli), 2 from Santa Maria de Dota, Costa Rica, 
shows full agreement. Further comparison of material con- 
vinces us that the West Indian series, recorded by Rehn and 
Hebard as E. ambigua, represents a distinct, though very closely 
related, species. 

1 Recorded in Ent. News, xxvi, pp. 463, 465 and 466, (1915). 

2 Recently received from Borelli, in exchange, by the Academy of Natural 
Sciences of Philadelphia. 



These species, with the South American Euborellia janeirensis 
(Dohrn), show a distinctive type of tegminal development, in 
which the aborted rounded tegmina cover all of the mcsonotum 
except the small median scutellar area, or all but a narrow 
median portion of the mesonotum. We refer them to what 
we term the Janeirensis Group. This type of tegmina in some 
respects resembles that developed in the Indian species Para- 
labis castetsi (Bolivar) and Epilabis penicillata (Borelli). Those 
species, however, have the tegmina much more transverse, with 
cephalic margins parallel to, and separated a distance from, the 
caudal margin of the pronotum, so that a narrow cephalic 
marginal portion of the metanotum is exposed, giving the ap- 
pearance of a very broad, but shallow, scutellar area. 

In order to avoid further confusion, we give, in the accompany- 
ing key, the more striking features of difference between the 
American species under consideration, following them with such 
additional data as is considered of value. 

Key to the Speeies of the Janeirensis Group 

A. Seventh to ninth abdominal tergites of male with latero-caudal 
angles sharply acute-angulate produced, weakly keeled and weakly rugulose. 
(Eighth and ninth abdominal tergites of female with latero-caudal angles 
roundly angulate produced, showing weak traces of keels distad.) Male 
forceps more distinctly bowed, as in Euborellia moesta (Gene) or the type of 
extreme specialization developed in annulipes] female forceps longer and 
more slender. Limbs unicolorous. (Antennae not annulate.) Caudal meta- 
tarsus no longer than combined length of the succeeding tarsal joints. (Size 
averaging large 3 , 12. 7 4 to 14 5 mm.). (Southern Florida and Costa Rica.) 

ambigua (Borelli) 
AA. Sixth to ninth abdominal tergites of male with latero-caudal angles 
very sharply acute-angulate produced, distinctly keeled and rugose. Male 
forceps weakly bowed, as is usual in annulipes; female forceps shorter and 
heavier. Limbs not unicolorous. Caudal metatarsus slightly but dis- 
tinctly longer than combined length of succeeding joints. 

3 Unless qualified the length given by us for Dermaptera is always that 
of the body, exclusive of the forceps. 

4 This is from the Costa Rican specimen before us; all of the Florida in- 
dividuals are larger. 

5 A body length of 16 millimeters is given in the original description. 


B. Antennae not annulate. Eight and ninth abdominal tergites of fe- 
male with latero-caudal angles rounded and rarely showing any trace 
of keel. Femora with external faces broadly washed with brown, this 
often weak; internal faces similarly washed with brown, this weaker and 
less extensive. Tibiae with ventral surface normally very weakly ting- 
ed with brown; this, when conspicuously developed, extending to near 
distal extermity. Size averaging small, 8.2 to 11.7 6 mm. (West 
Indies.) caraibea new species 

BB. Antennae annulate. Eighth and ninth abdominal tergites of 
female with latero-caudal angles roundly angulate produced and show- 
ing very weak keels. Femora with median portion of external faces 
suffused with brown, corresponding portion of internal faces usually with 
a suffused patch of this color. Tibiae weakly tinged with brown proxi- 
mad. Size averaging larger, 11.5 to 12.5 mm. (South America.) 

janeirensis (Dohrn) 

Euborellia ambigua (Borelli) (Plate XIX, figures 1, 2 and 3.) 

1906. Anisolabis ambigua Borelli, Boll. Mus. Zool. Anat. comp. Univ. 

Torino, xxi, no. 531, p. 3. [ 9 ', Hio Jesus Maria, in mangrove region, 

Costa Rica.] 

Santa Maria do Dota, Cos la Rica, 1 9, [A. N. 8. P.l. 

BriekeH's Hammock, Miami, Florida, II, 28 and III, G, 11)19, 
(M. Hebard; in mangrove swamp), 5a 71 , 3 9,1 juv., [Hebard 

The hitherto unknown male sex of this species may be readily 
recognized by the figures and the characters given in the key. 
In ambisexual features it agrees closely with Borelli 's adequate 
description of the female. We would note, however, that the 
pronotum, though widening evenly caudad, is there not as wide 
as the width of the head across the eyes. Borelli has stated 
"Pronoto . . . posteriormente di larghezza uguale a quella 
del capo." 

At the coastal localities where it has been found the species 
is known only from mangrove swamps. It will probably be 
found to have a wide distribution in that environment, when 
such situations, difficult of access and usually harboring swarms 
of mosquitoes, have been more extensively and carefully ex- 

6 Length of body, including forceps, of this largest specimen, from Porto 
Rico, 13.5 mm. 



Euborellia caraibea new species (Plate XIX, figures 4, 5 and 6.) 
1917. Euborellia ambigua Rehn and Hebard (not Anisolabis ambigua Borelli, 
1906), Bull. Am. Mus. Nat. Hist. ; xxxvn, p. 638. [9, cf ; Nassau, New 
Providence Island, Bahamas; Jesus del Monte, Cuba; Stony Hill and 
Montego Bay, Jamaica; Roseau, Dominica.] 

Previous to the records noted above, incorrectly referred to 
ambigua, material of the species had been recorded at different 
times as annulipes and janeirensis. Specimens of caraibea from 
Porto Rico are in the Philadelphia Collections, while Borman's 
record of janeirensis from St. Vincent 7 is almost certainly ref- 
erable to this species. 

The most important features of difference between caraibea 
and its nearest allies are given in the accompanying key, and 
are shown by the figures. The following additional characters 
are noteworthy. 

Type. — d"; Nassau, New Providence Island, Bahamas. Feb- 
ruary 3, 1914. (M. Hebard.) [Hebard Collection, Type no. 

Form moderately stout, as in janeirensis, slightly heavier than in ambigua. 
Antennae with longest distal joints not over twice as long as wide, in janeirensis 
about two and one-half times as long as wide, in ambigua fully three times 
as long as wide. Pronotum with length equal to width as in janeirensis, 
slightly shorter than in ambigua. Abdomen generally impresso-punctulate, 
this slightly heavier than in janeirensis; in ambigua the abdomen is almost 
smooth, showing much finer impressed punctulations laterad and distad. 

Ultimate abdominal tergite with a distinct, impressed, medio-longitudinal 
line; the surface slightly more tumid laterad than in janeirensis and ambigua. 
Forceps much as in males of janeirensis; short, stout, triquetrous proximad, 
straight to the incurved apices, the sinistral arm being less strongly incurved 
distad than the dextral arm, internal margin bluntly subserrulate. Penul- 
timate abdominal sternite triangularly produced, with apex rather broadly 

Allotype. — 9 ; same data as type. [Hebard Collection.] 
Agrees with male in features given above, except as follows. Ultimate 
abdominal tergite showing weak convexity dorso-laterad. Forceps much as 
in females of janeirensis; shorter than in male, stout, triquetrous proximad, 
straight to the weakly incurved apices, the sinistral and dextral arms being 
incurved to an equal degree, the nearly attingent ventro-internal margins 
slightly more coarsely but as bluntly subserrulate as in male. 

The measurements of the type and allotype are as follows. Length of 
body, d 1 10.2, 9 10.3; length of pronotum, cT 1.43, 9 1.56; caudal width of 
pronotum, d 71 1.43, 9 1.56; length of tegmen, tf 1.16, 9 1.29; width of tegmen, 

7 Proc. Zool. Soc. London, 1892, p. 201, (1892). 


d 1 .88, 9 .98; length of forceps, cf 1.9, 9 2.24; greatest (proximal) width of 
arm of forceps, d 71 .79, 9 .85 mm. 

General coloration shining, blackish with an auburn tinge. Antennae 
auburn, the proximal joints very slightly paler. Limbs warm buff, marked 
as described in key. 

In addition to the type and allotype, a pair bearing the same 
data, in the Hebard Collection, and a female, from the same 
locality, taken in the spring of 1904, by W. M. Wheeler, in the 
Academy of Natural Sciences Collection, are designated para- 

The following previously unrecorded material is before us : 

Cape Haitien, Hayti, (W. M. Mann), 1 9 , [Mus. Comp. Zool.]. 

Momance, Hayti, XI, 1912, (W. M. Mann), 1 9 , [Hebard Cln.]. 

St. Marc, Hayti, I, 1913, (W.M.Mann), 1 d\ [Mus. Comp. 

Arecibo, Arecibo, Porto Rico, VII, 30 to VIII, 1, 1914, (Lutz, 
Mutchler, Watson; under bark of rotten stump and under logs), 

1 cf , 1 9 , [Acad. Nat. Sci. Phila.]. 

Utuado, Arecibo, Porto Rico, (W. M. Wheeler), 1 d\ 3 9, 
[Amer. Mus. Nat. Hist.]. 

Banos de Coamo, Ponce, Porto Rico, (W. M. Wheeler), 1 c?, 

2 9,3 juv., [Amer. Mus. Nat. Hist.]. 

Aibonito, Ponce, Porto Rico, VI, 1 to VII, 17, 1914 and 1915, 
(Lutz, Mutchler, Barber; in rotten logs), 1 d\ 2 9 , [Amer. Mus. 
Nat. Hist.]. 

Port of Spain, Trinidad, III, 4, 1910, 1 cf, [Acad. Nat. Sci. Phila.] 
The last is the southernmost locality known for the species. 

Euborellia janeirensis (Dohrn) 

1864. F [or cinella] janeirensis Dohrn, Stettin Ent. Zeit., xxv, p. 285. [d"; 
Rio de Janeiro, Brazil.] 

Two males and three females from Gear a Mirim, Rio Grande 
do Norte and Independencia, Parahyba, Brazil, correctly re- 
corded as this species by Rehn, 8 have been used as the basis 
for the comparisons made in the present paper. 

« Trans. Am. Ent. Soc, xlii, p. 218, (1916). 



Explanation of Plates 
Plate XVIII 

Mangrove swamp on edge of Brickell's Hammock, Miami, Florida. Habi- 
tat of Euborellia ambigua, Hygronemobius alleni, Anaxipha scia and other 

Fig. 1. — Looking into swamp from seaward border. Tidal litter shown 
in foreground, beneath which Euborellia ambigua occurred. 

Fig. 2. — Seaward border of swamp, looking out toward Biscayne Bay from 
the same spot shown in figure 1. The mangrove shoots shown in the lower 
right-hand corner were the preferred habitat of Anaxipha scia, while beneath 
the tidal litter at their bases Euborellia ambigua was found. 

Plate XIX 

Fig. 1. — Euborellia ambigua (Borelli). Brickell's Hammock, Miami 
Florida. Dorsal outline of male. ( X 3) 

Fig. 2. — Euborellia ambigua (Borelli). Brickell's Hammock, Miami, 
Florida. Lateral view of distal portion of male abdomen. (X 4) 

Fig. 3. — Euborellia ambigua (Borelli). Brickell's Hammock, Miami. 
Florida. Dorsal view of distal portion of female abdomen. ( X 4) 

Fig. 4. — Euborellia caraibea new species. Nassau, New Providence Island, 
Bahamas. Type. Dorsal outline of male. (X 3) 

Fig. 5. — Euborellia caraibea new species. Nassau, New Providence Island, 
Bahamas. Type. Lateral view of distal portion of male abdomen. ( X 4) 

Fig. 6. — Euborellia caraibea new species. Nassau, New Providence Island, 
Bahamas. Allotype. Dorsal view of distal portion of female abdomen. 

















Trans. Am. Ent. Soc. Vol. XL VII.